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1.
本文主要通过对比分析研究热泉软泥中的金含量与有机质及含硫化合物的相关性。并测定泉水及软泥中含金量和软泥中有机碳含量,以及对抽提物中的饱和烃和芳烃族组分进行色谱—质谱分析,最后得出的结论:有机质的沉积环境为还原—强还原,有机质属于腐泥-腐殖型,接近和达到了成熟阶段。软泥中金含量与有机质的性质无明显相关关系,与有机碳含量也无明显相关关系,而与其成熟度相关密切。样品分析证实软泥中含硫化合物与金含量呈正相关性。对比分析了水及软泥中金含量,认为两者之间也无明显相关关系  相似文献   
2.
碟形弹簧竖向减震体系的分析与研究   总被引:1,自引:0,他引:1  
对碟形弹簧竖向减震体系利用时程分析方法对其进行动力分析,并输入不同场地、不同频谱的地震波考察其减震效果,验证了碟形弹簧在合理控制其刚度的前提下可以起到有效减小竖向地震的作用。  相似文献   
3.
Pamukkale thermal waters (35 °C), exhibiting calcium-bicarbonate-sulfate composition and high carbon dioxide concentration, are of a predominantly meteoric origin. The meteoric fluid, circulating through faults and fractures, is heated by magmatic intrusions at great depth, and ascends from deep reservoirs to the surface. Mixing with relatively cold groundwater in the near surface zone promotes different saturation conditions with respect to calcium carbonate that later precipitates at depth and/or the surface. Dissolution-deposition processes of calcium carbonate both at surface and depth environments may help to reconstruct past climate direction in the field. During wet climate conditions a high-rate of calcium carbonate accumulation would be expected to occur at the surface because thermal fluid would be under-saturated with respect to calcium carbonate at depth because of a relatively higher mixing ratio with cold groundwater. During dry climate conditions the thermal fluid would be super-saturated at depth because of the highly acidic environment. Hydrometeorological studies reveal that the annual precipitation at the Pamukkale hydrothermal field tends to decrease with time. This climatic change in the area was also detected from geological records. While humid climate conditions prevailed during the late Quaternary, the area has recently been affected by arid/semi-arid climate conditions, followed by some episodic transitions. This study has shown how the system has possibly reacted to different climate conditions since antiquity.  相似文献   
4.
泉水动态分析预测和资源评价——以辉县百泉为例   总被引:6,自引:2,他引:6  
本文通过对辉县百泉泉水流量动态的分析,确定了泉水流量动态的影响因素,建立了泉水流量的衰减方程和泉水流量的预测模型,预测了天然状态泉水流量,评了泉域岩溶水的开采资源。  相似文献   
5.
以重庆市南川区柏树湾表层岩溶泉溪流为例,沿柏枝溪流程以一定间距监测水体中HCO3-的浓度及其pH、电导率、溶解氧等水化学参数,并初步探究溪流水的脱气效应。结果显示(1)表层岩溶地下水出露地表后,HCO3-浓度沿流程呈现出递减的规律;(2)HCO3-浓度递减的快慢反映了脱气作用的强弱,溪流脱气速率具有“枯水期>平水期>丰水期”的特点;(3)暴雨期间由于稀释效应HCO3-浓度递减趋势不明显,但降雨后期,递减又开始逐渐产生;(4)脱气效应在造成溪流水HCO3-浓度减小的同时,也导致电导率(EC)沿柏枝溪流程逐渐降低,而pH值逐渐升高;(5)沿途溶解氧(DO)昼夜变化表明,水生生物作用对脱气作用可能也有一定的影响,但其影响机制还有待进一步的研究。   相似文献   
6.
Mounds that have formed around spring vents occur in a variety of environmental settings, many at sites generally difficult or inaccessible for sampling. In contrast, over 500 tufa mounds occur in the dry bed of Searles Lake, California. The mounds range from minor features to 45 m in height; most are 5 to 12 m high. These mounds, composed of calcite and aragonite, formed associated with spring vents in the Pleistocene lake bottom. Thus, analyses of these mounds in Searles Lake provide a model with regard to the origin and architecture of tufa mounds. The mounds consist of four distinctive tufa facies. The initial deposits consist of porous tufa, including the innermost (porous 1) and the outermost (porous 2) deposits, followed by nodular tufa, then columnar tufa, and laminated crusts. There are two simple sequences of tufa deposition. The first sequence is from porous 1 to nodular to laminated crusts and, finally, to porous 2. A second sequence consists of: porous 1 to columnar to laminated crusts and, lastly, to porous 2. Facies changes are a response to changes in environmental conditions from deep water (porous 1 facies) to an essentially dry lake phase (during and after the formation of laminated crusts facies), to deep water (porous 2 facies) and, at the present time, totally dry. The primary constituents that comprise the tufa deposits include thin laminae, pisoids, spherulites, peloids and stromatolite‐like crusts. On the microscopic scale, these constituents dominantly make up nano‐spheres, micro‐rods and rod‐like crystals, as well as other calcified bodies. These constituents are interpreted to be the calcified remains of bacterial bodies. These findings suggest that microbial participation in the construct of other mounds should be a major concern of investigation, both for terrestrial and extraterrestrial spring‐fed mounds.  相似文献   
7.
多普勒天气雷达站址视程的客观分析技术   总被引:11,自引:0,他引:11       下载免费PDF全文
开发了多普勒天气雷达候选站址视程的客观分析软件.该软件根据候选站及其四周一定范围内的地理信息, 十分快速地求算和自动绘制雷达单站的遮蔽角图、系列等射束高度图和多个雷达站Mercator或Lambert投影方式下的等射束高度拼图, 提供了分析和评价候选站雷达有效视程和相关雷达网共同覆盖效果以及定量应用雷达资料的客观工具.  相似文献   
8.
利用常规观测的温度资料和中国国家气候中心提供的环流特征量、NCEP/NCAR再分析资料及美国气候预测中心(CPC)提供的AO指数等,分析了2009年11月至2010年4月中高纬大气环流异常特征,探讨了AO与同期气温的关系。分析表明:黑龙江省冬春气候异常与500 hPa大尺度环流背景有关。冬春持续偏冷,对应北半球欧亚中高纬地区呈“-+-”的波列分布,90°-180°E呈现出“北正南负”的环流形势;北半球极涡面积偏大,冬季东亚大槽位置偏西,春季东亚大槽强度偏强,冬春AO指数持续异常偏强,显著负位相。  相似文献   
9.
通过对我国东南象限冬、春季雨带的相关分析,发现当冬、春季之间地气形势稳定时,约有68%的春雨带位于冬雨带南方50~300 km的范围内,此统计结果可作为预报春雨的指标;当冬季地气形势出现“双跳型”时,冬、春季之间的雨带可相距500 km以上,此时冬、春季的地震时空变化有可能作为春雨位置的预报指标。  相似文献   
10.
Lake Baikal is facing several environmental stressors, including climate change and nearshore eutrophication. To assess recent ecological changes in Lake Baikal and provide a baseline for future comparisons, we sampled spring plankton communities from the pelagic zone of the lake in 2016 and compared these data with unpublished and published historical information going back to 1990. In 2016, one pelagic long-term monitoring station was sampled in early spring (March) during ice cover and 21 long-term monitoring stations located throughout the lake were sampled in late spring (May-June). We measured water chemistry parameters at most stations and the abundance, taxonomic composition and biomass of bacteria, ciliates and phytoplankton at several locations in different areas of the lake. Biotic parameters from 2016 were compared with historical data, showing significant changes in the spring pelagic microbial community since the 1990s. We show increased quantities of small species, mixotrophic ciliates, and the appearance (or increasing number) of small coloured and colourless flagellates. We also show substantially decreased densities of formerly dominant heavily silicified diatoms such as Aulacoseira spp. Since 2007, Synedra acus subsp. radians, a smaller and weakly silicified diatom, has dominated the spring plankton of the lake. These results suggest that Lake Baikal’s pelagic plankton community may be changing, with climate likely playing a dominant role in these changes.  相似文献   
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